721742886 has 20 divisors (see below), whose sum is σ = 1617239052. Its totient is φ = 240580908.

The previous prime is 721742849. The next prime is 721742893. The reversal of 721742886 is 688247127.

721742886 is a `hidden beast` number, since 7 + 217 + 428 + 8 + 6 = 666.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 2227440 + ... + 2227763.

Almost surely, 2^721742886 is an apocalyptic number.

721742886 is an abundant number, since it is smaller than the sum of its proper divisors (895496166).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

721742886 is a wasteful number, since it uses less digits than its factorization.

721742886 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4455217 (or 4455208 counting only the distinct ones).

The product of its digits is 301056, while the sum is 45.

The square root of 721742886 is about 26865.2728629359. The cubic root of 721742886 is about 897.0035681786.

The spelling of 721742886 in words is "seven hundred twenty-one million, seven hundred forty-two thousand, eight hundred eighty-six".